|Publication number||US20070208371 A1|
|Application number||US 11/655,779|
|Publication date||Sep 6, 2007|
|Filing date||Jan 18, 2007|
|Priority date||Jun 29, 2000|
|Also published as||US8579915, US20120143231, WO2008088920A2, WO2008088920A3|
|Publication number||11655779, 655779, US 2007/0208371 A1, US 2007/208371 A1, US 20070208371 A1, US 20070208371A1, US 2007208371 A1, US 2007208371A1, US-A1-20070208371, US-A1-2007208371, US2007/0208371A1, US2007/208371A1, US20070208371 A1, US20070208371A1, US2007208371 A1, US2007208371A1|
|Inventors||Ron French, Scott Wilson, Neil Barman, Emily Vu, John Miller|
|Original Assignee||Concentric Medical, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Referenced by (10), Classifications (13), Legal Events (1)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present application is a continuation-in-part of application Ser. No. 11/250,190, filed on Oct. 13, 2005 which is a continuation-in-part of application Ser. No. 10/460,751, filed Jun. 11, 2003 which is a continuation-in-part of application Ser. No. 10/055,714, filed Jan. 22, 2002 which is a continuation-in-part of application Ser. No. 09/891,141, filed Jun. 25, 2001, which is a continuation in part of application Ser. No. 09/756,476, filed Jan. 8, 2001, which is a continuation-in-part of application Ser. No. 09/605,143, filed Jun. 29, 2000, the full disclosures of which are incorporated herein by reference for all purposes.
1. Field of the Invention
The present invention is also directed to methods and devices for removing obstructions from blood vessels. The device may be used to retrieve and remove clots and other biological obstructions or to retrieve embolic coils and the like which have been misplaced or have migrated to an undesirable location.
Obstruction removal devices are disclosed in U.S. Pat. Nos. 5,895,398 and 6,824,545, which are hereby incorporated by reference.
The present invention is directed to methods and devices for removing obstructions from blood vessels. The device may be used to retrieve and remove clots and other biological obstructions. The device may also be used to retrieve embolic coils and the like which have been misplaced or have migrated to an undesirable location.
One such obstruction removal device is disclosed in U.S. Pat. No. 5,895,398 which is hereby incorporated by reference. The device has an expandable engaging member which is introduced into the blood vessel to engage the obstruction for removal.
The present invention is also directed to devices, systems and methods which use an expandable capture element when removing obstructions from a blood vessel. One such system for removing obstructions in a blood vessel is described in U.S. Pat. No. 5,102,415 to Guenther et al. The system described in U.S. Pat. No. 5,102,415 has a balloon catheter and a catheter having an expandable tip which receives the obstruction. The balloon catheter is passed through the obstruction while the balloon is deflated. The balloon is then inflated and the tip of the catheter is expanded. The balloon is then moved proximally so that the obstruction is pulled into the expanded tip of the catheter. A problem with the system of U.S. Pat. No. 5,102,415 is that the interaction between the balloon catheter and the leading edge of the catheter may tend to shear off portions of the obstruction. This can cause obvious problems when working in sensitive vascular areas.
The present invention is directed to additional devices and methods for removing obstructions in a blood vessel.
In a first aspect of the present invention, a method of forming an obstruction removing element is also described. The method includes use of a two part mandrel with at least one of the mandrels being movable relative to the other mandrel. An elongate element is wrapped around the first mandrel and then the second mandrel is moved to a position closer to the first mandrel. The elongate element is then wrapped around the second mandrel to complete the desired shape. The elongate element may be wrapped over an end of the first mandrel so that the elongate element extends over an apex of the first mandrel and intersects the longitudinal axis of the first mandrel.
In another aspect of the present invention, a device and method for removing an obstruction are described. The obstruction removing device has at least two loops defining a longitudinal axis at a proximal section or distal section or both. An intermediate section has two crossing portions which intersect the longitudinal axis. The device is introduced into a patient and then used to engage and remove the obstruction.
In accordance with the present invention, device and methods for removing obstructions are also provided. In a first aspect of the invention, an obstruction removal device is provided which has an obstruction engaging element extending from an insertion element. The engaging element is movable from a collapsed position to an expanded position. The engaging element forms coils having varying diameter wherein the coils at a distal portion are larger than coils at an intermediate portion. The distal portion forms a relatively closed structure which prevents the obstruction, or any part thereof, from migrating downstream. The distal portion is expanded distal to the obstruction while the proximal portion engages and holds the obstruction.
In another aspect of the present invention, another obstruction removal device is provided which has at least one closed loop and preferably two closed loops. The closed loop provides an advantage when advanced through a catheter or sheath in that the closed loop produces opposing radial forces on the catheter or sheath through which the loop is advanced. In this manner, the obstruction removal device can be advanced more easily through the catheter or sheath to prevent binding or kinking of the device during advancement. In a preferred embodiment, the obstruction removal device has two loops of varying diameter with the distal loop having a larger diameter. Each of the loops lie in a plane with the planes of the two loops preferably being perpendicular to one another.
In another aspect of the invention, another obstruction removal device is provided which has wound sections formed by one or more filaments which are separated by sections substantially free of the filaments. The intermittent wound sections provide discrete portions where the obstruction can be engaged. In an embodiment, the wound sections can slide on the core element to provide flexibility when advancing the obstruction removal device. The wound sections and sections free of filament are preferably about 1-5 mm long. The obstruction removal device preferably has at least three wound sections and more preferably at least five wound sections.
In still another aspect of the invention, another obstruction removal device is provided which has alternating large and small diameter portions. In a preferred embodiment, the obstruction removal device has at least four large diameter sections and three smaller diameter portions. The alternating large and small diameter portions may help to engage certain types of obstructions and can also help to prevent parts of the obstruction from breaking off and migrating downstream.
Any of the obstruction removal devices described herein may also be used with a source of power coupled to the obstruction removal device for use as described below. The source of power may simply produce a positive or negative charge or may be an RF energy source. The source of power may be used to help the obstruction removal device penetrate and engage the obstruction and may also be used to adhere the obstruction to the obstruction removal device as will be described. In a preferred embodiment, a negative charge is provided when advancing the obstruction removal device into the obstruction and a positive charge, or RF energy, is supplied to adhere the device to the obstruction.
The devices of the present invention may be manufactured in any suitable manner. In another aspect of the present invention, the obstruction removal device has a core element surrounded by a sheath. A strand, preferably about four strands, are positioned between the core element and the tube. The strand and the tube prevent any part of the obstruction removal device from breaking free should the core element fail. The strand and tube will hold the obstruction removal device together even if the core element breaks. The sheath is preferably flexible so that the sheath can undergo much larger deflections than the core element.
The obstruction removal devices of the present invention may also be advanced through a guide catheter having a flow restricting element which is preferably a balloon but may be any other suitable structure. The flow restricting element is expanded to reduce blood flow through the obstructed vessel to minimize the likelihood that the obstruction will migrate downstream.
In another aspect of the invention, a system is provided which has an expandable capture element and an obstruction engaging device which together work to remove an obstruction from a blood vessel. The capture element is advanced through the patient in a collapsed position and is expanded when at the desired location. The obstruction engaging device preferably has one or more filaments which provide a relatively flexible interaction between the engaging device and the capture element. This provides advantages over the use of a balloon catheter as described in greater detail below. The obstruction engaging device preferably has 1-4 filaments and more preferably 1-2 filaments. Of course, the obstruction engaging device may have more filaments without departing from various aspects of the invention and, in fact, the device may form a filter which further helps to prevent portions of the obstruction from being carried downstream.
The capture element is preferably naturally biased toward the expanded position although the capture element may also be manually actuated as described below. The capture element has a support structure with a flexible cover attached thereto. The support structure preferably has a closed loop which opens the distal end of the cover. The loop is preferably integrally formed and has a number of integrally formed hinges which deflect when the loop is expanded and collapsed. The hinges are preferably V-shaped although other shapes may be used. A plurality of struts extend proximally from the loop.
The capture element may also be expanded by the user so that the user may select the appropriate time for expansion of the capture element. In this manner, the user may advance the capture element to a suitable location for expansion. The user may also collapse the capture element before withdrawing the capture element into a catheter. The capture element has an actuator for opening and closing the capture element. The actuator may have a control arm and a stable arm although any suitable actuator may be used. The control arm is manipulated to expand and contract a loop at the distal end of the capture element. Alternatively, the actuator may be a tube which cinches the loop closed. In a specific embodiment, the capture element may also evert when moving to the expanded position.
The device of the present invention may be used in various different locations and for various different purposes. In one embodiment, the device may be used in connection with a guide catheter. When used with the guide catheter, the device may be expanded to slow or even stop blood flow when performing other procedures downstream of the guide catheter such as removing a clot or placing a stent.
Alternatively, the device may be passed through a conventional guide catheter so that the device may be introduced further into the vasculature. In this system, the capture element passes through the guide catheter. The obstruction engaging device is then used to engage the obstruction and move the obstruction into the capture element.
The present invention is also directed to methods and devices for removing an obstruction where the obstruction engaging element has a shape which traps the obstruction. In one aspect, the element extends proximally and then distally to ensnare the obstruction. The element may have such a shape naturally or may be moved into this shape by manipulating the element. For example, the element may be rotated in one or both directions to ensnare the obstruction. The element may have a portion which prolapses to capture the element as the element is manipulated.
In still another aspect of the invention, the capture element inverts when the obstruction is moved into the capture element. The obstruction is preferably engaged with an engaging element having a filament which ensnares the obstruction. The obstruction engaging element may be independent from the capture element or may be connected to the engaging element. The capture element inverts upon application of a compressive force to the inverting portion or upon any other suitable actuation force. The capture element preferably inverts when the compressive force is applied by either the obstruction or the engaging element.
The present invention is also directed to actuators for medical devices. In a first aspect, an actuator is provided which has an outer member and a plurality of fingers extending from the outer member. The fingers form an end that can be opened and closed by bending and straightening the fingers. The fingers may be bent by moving an inner member coupled to the fingers or by tensioning or releasing tension on a filament. The medical devices described above may be used for any suitable purpose including capture or containment of obstructions. For this purpose, the fingers or frame may be covered with the cover that forms an enclosure to hold the obstruction.
In another aspect, the medical device may have a frame that extends from inner and outer members. The frame forms an end that also opens and closes. The frame has a first set of connectors coupled to the outer member and a second set of connectors coupled to the inner member. The inner and outer members are movable relative to one another to open and close the end. The frame may be an integral structure with the structure being deformed when the end opens and closes. In still another aspect, the frame may be made of a shape memory material which regains either the closed or open position when heated or cooled. For example, the frame may be heated using electrical energy or other suitable source to actuate the frame.
In still another aspect of the present invention, a device and method for removing an obstruction from a blood vessel is provided. A strand extends along the elongate obstruction removing element and extends between the coils of the element. The element may be manipulated to entangle the main element with the strand and to entangle the device with the obstruction. The strand will become entangled with the element at locations dependent upon permitted expansion of the element within the blood vessel.
In yet another aspect, an intravascular device and method for removing material from a vascular site are provided. A filament is wrapped around the main element in a delivery condition. The filament and main element are then rotated relative to one another to cause the two to essentially unravel.
In yet another aspect of the present invention, an obstruction removing element is provided which has a plurality of expandable structures formed by the elongate element. The expandable structures are formed so that adjacent structures wind in opposite directions when viewed along the longitudinal axis of the device. The expandable structures may wind to form a substantially closed structure. To this end, the expandable structure may wind about 360 degrees when viewed along the longitudinal axis. Of course, the expandable structure may wind a bit more or less than 360 degrees such as 315-405 degrees.
These and other advantages of the invention will become apparent from the following description, drawings and claims.
Referring now to
An obstruction removing device 8 is advanced through the guide catheter 4 to the obstruction. A microcatheter 10 may also be positioned within the guide catheter 4 to deliver the obstruction removing device 8 further into the vasculature. The obstruction removing device may be advanced by itself through the microcatheter 10 or may be contained within a sheath 12 which is advanced through the microcatheter 10. A source power 14 may also be coupled to the obstruction removal device 8 for use in the manner explained below. The power source 14 may simply produce a positive or negative charge or may be an RF or other suitable power source.
The obstruction removing device 8 has an engaging element 16 extending from an insertion element 18. The engaging element 16 is movable from a collapsed position (
An advantage of the obstruction removal device 8C is that the loops 50, 52 exert substantially equal and opposing forces on the sheath 12 or microcatheter 10 through which the obstruction removal device 8C is advanced. In this manner, kinking or binding of the obstruction removal device 8C during advancement can be minimized or reduced altogether. Referring to the end view of
Another method of aiding mechanical capture of an obstruction is to coat the device and elements of the present invention with a material 61 which helps to adhere the obstruction, and in particular thrombus, to the device or element. The material 61 is preferably fibrin but may be any other suitable material. Use of the material 61 may be incorporated into any of the devices described herein or other suitable device such as the devices shown in
When the element initially expands, the coils 274 do not overlap when viewed along a longitudinal axis L. The element 270 is then engaged by manipulating the element 270. After the obstruction has been engaged, the element 270 is rotated which tends to open the coils 274. This causes one or more proximal coils 274 to prolapse over other coils to ensnare the obstruction. Stated another way, the element 270 initially extends distally in a relatively continuous manner. After rotating the element 270, the element extends distally, then proximally, then distally again. Stated yet another way, the coils are manipulated so that they appear to overlap when viewed along the longitudinal axis L. The prolapsed or overlapping coils 274 may provide an even more secure engagement to the obstruction. The element 274 may also be formed to have the overlapping or prolapsed sections when in the natural, unbiased and expanded position as shown in
Referring now to
Still another device 300 is shown in
Referring now to
Referring now to
The main element 904 may be any suitable element 904 which is naturally biased toward the expanded position such as any of the elements described herein.
The strand 906 may be any suitable filament, wire, fiber, monofilament and may be made of any suitable material such as nylon, polypropylene, polyester, polyurethane, silicone, latex, a liquid crystal polymer (LCP) such as Vectran or even nitinol or stainless steel. The strand 906 is flexible and may not have a predetermined shape with the strand 906 being deformed and deflected by the element 904 as the element 904 expands. The element 904 includes two strands 906 which interlock or have interlocking loops 908 at about the midpoint of the expandable portion of the element 904. Stated another way, the strands 906 form two loops 908 which interlock at the midpoint as shown in
Referring again to
Use of the devices 902 of
The device 900 may emerge from the delivery catheter 905 with the strands 906 being relatively free of the main element 904 between the proximal and distal attachments to the main element. Of course, the strands 906 may be interwoven, looped around or even somewhat entangled with the main element 904 so long as the user may manipulate the device to further entangle the strand 906 and element 904. Rotation of the device causes the strands 906 to become entangled with the main element 904 in a manner dictated by the geometric restrictions of the vessel and obstruction. The device itself may also become more entangled with the obstruction during rotation of the main element 904. An advantage of using the helical or coiled structures described herein is that rotation of the main element 904 not only causes the device to engage the obstruction but also causes the strand 906 to become entangled with the main element 904.
Another aspect of the present invention is that the amount of entanglement between the strand 906 and element 904 may be controlled. For example, the user may first attempt to remove the obstruction with little or no rotational manipulation of the element 904. The user can then pull on the main element 904 and determine whether the device can remove or dislodge the obstruction or whether the main element is disengaging or slipping relative to the obstruction. Disengagement can occur due to excessive elongation or distortion of the main element 904 or may be simply due to poor engagement between the device and obstruction. The user may then rotate or otherwise manipulate the device to cause further entanglement between the strand 906 and element 904 and between the device itself and the obstruction. Increasing the entanglement between the strand 906 and main element 904 may help to reinforce the main element which can reduce stretching and distortion of the main element 904 when the main element 904 is tensioned. The strands 906 also increase the overall surface area of the device and generally reduce the size of interstitial spaces in the main element 904. Another aspect of the present invention is that the strand 906 and element 904 may engage one another at locations dependent upon the permitted expansion of the main element 904 within the vessel. As such, the present invention provides advantages over conventional mesh-like structures having a predetermined geometry since these structures may not perform adequately under a variety of different size restrictions in an obstruction.
Although the strand 906 and element 904 may not be substantially entangled when the element is initially expanded, the main element 904 and strand 906 may also be designed to become entangled with one another during expansion of the main element 904. For example, the element 904 may naturally begin to twist in a helical manner to form coils 908 when expanding. The twisting motion causes the strand 906 to engage, contact and and/or otherwise entangle itself with the element 904 and obstruction. The strand 906 will engage the element 904 at a number of locations dependent upon the manner in which the element expands within the vessel as described above. Although the element 904 generally follows a helical path when expanding, the element 904 may expand in any other manner which tends to entangle the strand 906 and element 904. For example, the element 904 may rotate one way and then another or may be longitudinally displaced or reciprocated. Thus, it can be appreciated that the element may expand in a number of different ways to cause the strand 906 to become entangled with the element. Of course, the element may also be rotated or otherwise manipulated to enhance entanglement between the strand 906 and element even after expansion of the main element to provide the advantages described above.
After the obstruction has been engaged by the device, the main element is pulled to dislodge the obstruction for removal as describe above. Once the element has dislodged the obstruction, the obstruction may be moved into a guide catheter 909 or sheath for removal from the patient. The guide catheter 909 may have a balloon to occlude blood flow during withdrawal of the obstruction.
The filaments 922, 924 may be twisted relative to one another so that they can unwind by manipulating one or both filaments as shown in
The device 500 may also include a distal section 506 having one or more loops 508 wound in the same direction. The loops 508 may be formed so that residual stresses in the material bias the loops 508 toward one another. In this manner, the loops 508 preserve a tight pitch to engage and even clamp the obstruction as described below. The manner in which the loops 508 of the distal section 506 interact may also influence the configuration of one or more filaments 510 attached to the device 500.
The device 500 may also have a proximal section 512 positioned proximal to the expandable structures 502. The proximal section 512 may also have one or more loops 514 wound in the same direction with a relatively tight pitch. The proximal section 512 may help to surround the obstruction and may also pinch or trap the obstruction between adjacent loops 514 of the proximal section 512 or between the proximal section 512 and one or more of the expandable structures 502.
Referring now to
The devices 500, 530, 540 may also include one or more of the filaments 510 coupled to the elongate element 504. The filaments 510 may be positioned and configured in any manner described herein and the features and advantages of the filament 510 described herein and in the applications and patents incorporated herein by reference are expressly incorporated here. The filament 510 may be made of suture, polymer or even metal. The filament 510 may be coupled to the devices 500, 530 at any suitable proximal and distal location. For example, the filament 510 may be attached to the devices 500, 530 at a proximal location with the distal location being at a desirable circumferential or angular distance from the proximal attachment. The filament 510 may be sized to be substantially the same length as the distance between the proximal and distal locations on the elongate element when the elongate element 504 is straightened.
The devices 500, 530, 540 may be used in any manner described or incorporated herein and all such uses are expressly incorporated here. One method of using the device 500 is now described and it is understood that the method applies to devices 500, 530, 540. The device 500 is collapsed into a straightened configuration and advanced through the patient's vascular system to the obstruction. The device 500 may be maintained in the collapsed condition by a delivery catheter or sheath (see
The catheter is then retracted to expose the expandable structures 502. Due to the alternating winding directions of the expanding structures 502, the tip of the catheter does not need to make excessive revolutions around the obstruction. Instead, the tip may remain essentially within a 360 degree range as the device 500 is deployed. In this manner, the structures 502 may help wrap the device 500 around the obstruction without requiring the tip of the catheter to wind completely around the obstruction a number of times as may be necessary with other devices. The structures 502 may also help to push the obstruction away from the vessel wall since the structures 502 may cause the elongate element 504 to turn radially inward to better secure the obstruction.
Another system 103 for removing an obstruction from a patient is shown in
An obstruction removing element 100 is advanced through the guide catheter 4 to the obstruction. A microcatheter 10 may also be positioned within the guide catheter 4 to deliver the obstruction removing element 100 further into the vasculature. The obstruction removing element 100 may be advanced by itself through the microcatheter 10 or may be contained within a sheath which is advanced through the microcatheter 10.
The obstruction removing element 100 has an expandable portion 101 which is naturally biased to the expanded position shown in
Referring now to
The elongate element 102 essentially takes a shape of a groove 112 formed in the proximal and distal mandrels 104, 106. Thus, it is understood that when the groove 112 shape or the elongate element 102 shape is described, that the shape of the elongate element 102, or the groove 112, is also being described. Beginning with the groove 112 in the proximal mandrel 104, the groove 112 extends longitudinally until it reaches a coiled section 114 which forms 3 1/4 turns to form a proximal coiled section 115 in the elongate element 102. The groove 112 then turns distally and forms a first arc 116 over an apex 118 of the proximal mandrel 104. The groove 112 then forms a curved section 109 which winds the element 102 into position to form a second arc 120 over the apex 118. The groove 112 then turns distally before the proximal mandrel 104 is coupled to the distal mandrel 106.
The distal mandrel 106 is then engaged with the proximal mandrel 104 using the pin 108 and hole 110. The groove 112 includes another coiled section 122 having 2 3/4 turns which forms a distal coiled section 123 in the elongate element 102. Following the coiled section 122, the groove 112 then turns distally and extends longitudinally to complete the desired shape.
The first and second arcs 116, 120 form crossing sections 117, 121 in the elongate element 102 which intersect the longitudinal axis LA when viewed along the longitudinal axis as shown in
The elongate element 102 is wound around the mandrels 104, 106 using the keyhole sleeve 124 in the following manner. First, the keyhole sleeve 124 is placed over the distal end of the proximal mandrel 104 with the elongate element 102 positioned in the hole 126. The keyhole sleeve 124 is then manipulated so that the hole 126 essentially traverses the straight portion of the groove 112 so that the elongate element simply falls within the groove 112 and becomes trapped in the groove 1 12 by the sleeve 124. The keyhole sleeve 124 is then manipulated so that the hole 126 follows the coiled section 114 of the groove 112 in the proximal mandrel 104 to wind the element 102 around the mandrel 104. At this point, the groove 112 turns distally and forms the first arc 116 over the apex 118 of the proximal mandrel 104. When winding the elongate element 102 to create the first and second arcs 116 120, tension is maintained on the elongate element 102 and the keyhole sleeve 124 is positioned to permit the elongate element 102 to escape through the end of the slot 128. The element 102, which is now free from the hole 126 and slot 128 of the sleeve 124, is wrapped over the mandrel 104. The sleeve 124 is then rotated 180 degrees to align the slot 128 with the end of the arc 116, 120 to feed the elongate element 102 back into the keyhole sleeve 124. The distal mandrel 106 is then engaged with the proximal mandrel using the pin 108 and hole 110 engagement. The keyhole sleeve 124 is manipulated in substantially the same manner to cause the elongate element 102 to fall into the coiled section 122 of the groove 112 in the distal mandrel 106. Once the elongate element 102 is properly positioned in the groove 112, a distal sleeve 134 and/or proximal sleeve 136 may be advanced over the proximal or distal mandrels 104, 106 to help hold the elongate element 102 in place during heat forming.
Use of the obstruction removing element 100 is now described. The guide catheter 4 is introduced into the patient and delivered proximal to the target vessel such as to the carotid or vertebral artery. The microcatheter 10 is then advanced through the guide catheter 4 further into the vasculature to a position proximal to, within or distal to the obstruction. The obstruction removing element 100 is then advanced through the microcatheter 10 either by itself or pre-loaded within the sheath 12. The obstruction removing element 100 is then advanced to the obstruction. Before advancing the obstruction removing element 100 further, the flow restricting element 6 on the guide catheter 4 is expanded to reduce and even stop flow through the vessel. Stopping flow in the vessel may help prevent the obstruction, or any parts thereof, from migrating downstream. Reducing flow through the vessel may also reduce the likelihood that the obstruction is disrupted by a combination of flow and the obstruction removal device 8.
The microcatheter 10 is then advanced into the obstruction and the obstruction removing element 100 is then positioned so that part of the obstruction removing element 100 is within the obstruction while a portion, such as the distal coil section 123, are positioned distal to the obstruction. The obstruction removing element 100 is then moved out of the microcatheter 10 to permit the obstruction removing element 100 to expand by withdrawing the microcatheter and/or advancing the obstruction removing element 100. The obstruction removing element 100 is then manipulated to engage and dislodge the obstruction. The obstruction may then be removed by applying suction to the guide catheter 4 to hold and/or contain the obstruction for removal or with use of another suitable device.
Referring now to
When the element 100 expands within the vessel, the element 100 may also expand with the element 100 temporarily undergoing a rotary or helical motion so that the rotary or helical motion causes the strand to engage the element 100 in a manner dependent upon the expansion of the element 100. The element 100 of
While the above is a description of the preferred embodiments of the invention, various alternatives, substitutions and modifications may be made without departing from the scope thereof, which is defined by the following claims. Thus, the preferred embodiments should not be taken as limiting the scope of the invention. For example, although all of the obstruction removal devices described herein are self-expanding structures, the obstruction removal devices may also have actuating mechanisms for moving the engaging element between the expanded and collapsed positions. Furthermore, the present invention is directed to a number of separate inventions and each of these inventions may be claimed independently of one another. Each feature, aspect and advantage of the invention may be claimed independent of one another without departing from the scope of the invention.
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7951243||Jan 26, 2009||May 31, 2011||Clear Catheter Systems, Inc.||Methods and devices to clear obstructions from medical tubes|
|US8088140||May 29, 2009||Jan 3, 2012||Mindframe, Inc.||Blood flow restorative and embolus removal methods|
|US8945143||Jun 24, 2013||Feb 3, 2015||Covidien Lp||Expandable tip assembly for thrombus management|
|US8945172||Dec 30, 2011||Feb 3, 2015||Covidien Lp||Devices for restoring blood flow and clot removal during acute ischemic stroke|
|US8998945||Dec 16, 2009||Apr 7, 2015||Abbott Laboratories Vascular Enterprises Limited||Methods and apparatus for filtering a body lumen|
|US9039749||Oct 1, 2010||May 26, 2015||Covidien Lp||Methods and apparatuses for flow restoration and implanting members in the human body|
|US20050283166 *||Jun 14, 2005||Dec 22, 2005||Secant Medical, Llc||Expandible snare|
|WO2009105710A1 *||Feb 20, 2009||Aug 27, 2009||Micro Therapeutics, Inc.||Methods and apparatus for flow restoration|
|WO2010077966A1 *||Dec 16, 2009||Jul 8, 2010||Abbott Laboratories Vascular Enterprises Limited||Methods and apparatus for filtering a body lumen|
|WO2012081020A1 *||Dec 12, 2011||Jun 21, 2012||Perflow Medical Ltd.||Method and apparatus for occlusion retrieval|
|Cooperative Classification||A61B2017/2217, A61B17/22031, A61B2017/22035, A61B2017/22094, A61B17/221, A61B2017/2215, A61F2/013, A61B2017/2212, A61B2017/22034|
|European Classification||A61B17/22E, A61B17/221|
|Aug 15, 2007||AS||Assignment|
Owner name: CONCENTRIC MEDICAL, INC., CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FRENCH, RON;WILSON, SCOTT;BARMAN, NEIL;AND OTHERS;REEL/FRAME:019713/0743
Effective date: 20070403